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91.
Hiroshi Yamada Shizuo Oi Norihiko Tamaki Satoshi Matsumoto Katsuko Sudo 《Child's nervous system》1992,8(7):394-398
Primary aqueductal stenosis is one of the main causes of congenital hydrocephalus in humans and experimental models. The congenitally hydrocephalic rat strain LEW/Jms is one such model. In this report, we describe further detailed histological features of periaqueductal structure, including the posterior commissure, subcommissural organ (SCO), and ependyma, and discuss the changes in these structures in relation to the cause of hydrocephalus. Coronal sections of the aqueduct in normal rats showed that the usual ependyma was absent in the center of the base facing the dorsal side, which was replaced by tall columnar cells. On the other hand, in hydrocephalic rats the ependyma encircled the aqueductal cavity. In midline sagittal sections, normal and hydrocephalic rats showed the SCO, although the SCO in hydrocephalic rats was shorter than in normal rats. There was also a marked difference between normal and hydrocephalic rats in the dorsoventral dimension of the rostral midbrain. In hydrocephalus, this dimension was large in comparison with normal rats. The superior collicular commissure located caudal to the posterior commissure ran along the ventral side of the midbrain in rats with hydrocephalus, and there was a cell-depleted area just dorsal to the superior collicular commissure. The same findings were observed from the 17th day of gestation until the postnatal period. Although the role of the SCO has been widely discussed from the viewpoint of secretory function, the present study indicated that this organ might be involved in the formation of the shape of the aqueduct. 相似文献
92.
G. D. MacEwen Cl. Karger 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》1992,2(2):89-93
Résumé D'étiologie toujours inconnue, la scoliose idiopathique de l'adolescent ne peut être traitée efficacement que si le dépistage est très précoce, entre 8 et 10 ans. La preuve de l'évolutivité angulaire doit être faite avant d'entreprendre un traitement orthopédique, dont l'objectif sera de contrôler l'aggravation liée à la poussée de croissance pubertaire. De nouveaux protocoles à temps partiel sont actuellement à l'étude et s'adresseront à des courbures peu sévères et bien réductibles. Les indications opératoires sont posées en cas d'échec ou d'intolérance au traitement orthopédique. Les limites angulaires pour de telles interventions semblent diminuer progressivement, les techniques devenant plus fiables. On accorde par ailleurs de plus en plus d'importance au plan sagittal, compte tenu de la mauvaise tolérance à long terme des lordoses thoraciques. Malgré les progrès techniques, la réalisation d'une arthrodèse solide avec une greffe abondante reste le seul garant de la stabilité angulaire. L'évolution et l'histoire naturelle des courbures congénitales du rachis sont actuellement bien connues, ainsi que les malformations viscérales habituellement associées. La surveillance radiographique dès le plus jeune âge permet d'évaluer l'asymétrie de croissance vertébrale dans le plan frontal et sagittal. Ceci permet de proposer en cas d'évolutivité un traitement à visée étiologique précoce, sous forme d'une hémi arthrodèse et épiphysiodèse convexe, antérieure et postérieure pour freiner l'hypercroissance du côté de la malformation. Pour les formes dépistées plus tardivement, une greffe postérieure avec ou sans matériel est l'indication classique, en évitant absolument toute manoeuvre de distraction qui comporte un risque de complication neurologique, en particulier en cas de composante cyphotique associée.
Idiopathic and congenital scoliosis
Summary The exact etiology of idiopathic scoliosis is still unknown and therefore the only way to improve the prognosis is to recommend an early screening program, between 8 and 10 years of age. Angular progression must be proven for every curve before any brace application. The goal of such a treatment is to control curve progression during the adolescent growth spur. Recent part-time bracing programs have been proposed for low angle and flexible curves. Surgery is indicated in case of failure or non compliance of the conservative treatment. Currently the angular limits for surgery seem to decrease, as a result of improved surgical techniques. Sagittal unbalance and loss of thoracic lordosis are of major importance for the treatment choice, since their poor outcome in the adult population. Despite technical improvements, the quality of a solid fusion is the most important factor for long lasting results. The natural history and evolution of congenital spine deformities have been precisely documented, as well as the frequently associated visceral problems. Repeated curve measurements in young children will evaluate the growth potential asymetry in the coronal and sagittal planes. In case of rapidly progressive curves, an early surgical treatment can be proposed, consisting in convex anterior and posterior hemiarthrodesis, producing an epiphysiodesis effect of the overgrowing convex side. For cases diagnosed in older ages, the classic indication is a posterior fusion, with or without instrumentation. It is important to avoid any excessive distraction, because of a high risk of neurological complications, especially in case of an associated kyphotic deformity.
Travail présenté aux Actualités. en Orthopédie Pédiatrique organisées par le Dr Cl. Karger, le 19 au 21 mars 1992 à Aubure 相似文献
93.
P. Klein R. Anetsberger R. Stangl H. P. Hümmer 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1994,379(1):54-57
Zusammenfassung Eine hochgradige Duodenalstenose im Erwachsenenalter kann in seltenen Fällen angeboren sein und findet ihre Ursache in einer intraduodenal gelegenen Membran. Die Anamnese zeigt Wachstumsstörungen mit Erbrechen und Meteorismus und abdominelle Beschwerden. Eine Perforationsöffnung in dieser Membran ist die Ursache fur ein Überleben bis ins Erwachsenenalter. Die Röntgendarstellung und die tiefe Duodenoskopie lassen auf einfache Weise die Diagnose stellen. Differentialdiagnostisch müssen der Volvulus bei Malrotation, Ladd-Bänder und das Pancreas anulare, sowie die Kompression des Duodenums durch Mesenterialgefäße erwogen werden. Das operative Verfahren der Wahl ist die Resektion der intraduodenalen Membran. Dabei ist v. a. die Papilla Vateri darzustellen, da diese nicht selten im Bereich des Septums mündet. Das längs eröffnete Duodenum wird quer verschlossen. Bei der Wind-Sock-Web-Anomalie sollte das Duodenum an der Ansatzstelle des Diaphragmas eröffnet werden. Die Anlage einer Gastrojejunostomie ist inadäquat und zu vermeiden.
Congenital duodenal stenosis in adulthood
A high-grade duodenal stenosis in adults can, in rare cases, be congenital, and its cause is found in an intraduodenally sited membrane. The anamnesis reveals growth disorders with vomiting and meteorism and abdominal complaints. A perforation opening in this membrane is the reason for survival into adulthood. The X-ray appearance and deep duodenoscopy make the diagnosis easy. Volvulus in cases of malrotation, Ladd's ligaments, anular pancreas, and compression of the duodenum by mesenteric vessels must be considered in the differential diagnosis. When the intraduodenal membrane is resected it is most important to expose the papilla Vateri, since this not uncommonly ends in the area of the septum. If necessary, a duodenoduodenostomy is performed. If the windsock web abnormality is present the duodenum should be opened at the point of attachment of the diaphragm. The construction of a gastrojejunostomy should be avoided.相似文献
94.
JORGE M. DAVIDENKO M.D. MARIO DELMAR M.D. Ph .D. JACQUES BEAUMONT Ph .D. DONALD C. MICHAELS Ph .D. PACO LORENTE Ph .D. JOSÉ JALIFE M.D. 《Journal of cardiovascular electrophysiology》1994,5(11):945-960
Inhibition and Facilitation in Cardiac Muscle. Introduction: The effects of subthreshold electrical pulses on the response to subsequent stimulation have been described previously in experimental animal studies as well as in the human heart. In addition, previous studies in cardiac Purkinje fibers have shown that diastolic excitability may decrease after activity (active inhibition) and, to a lesser extent, following subthreshold responses (electrotonic inhibition). However, such dynamic changes in excitability have not been explored in isolated ventricular muscle, and it is uncertain whether similar phenomena may play any role in the activation pal-terns associated with propagation abnormalities in the myocardium. Methods and Results: Experiments were performed in isolated sheep Purkinje fibers and papillary muscles, and in enzymatically dissociated guinea pig ventricular myocytes. In all types of preparations introduction of a conditioning subthreshold pulse between two subthreshold pulses was followed by a transient decay in excitability (electrotonic inhibition). The degree of inhibition was directly related to the amplitude and duration of the conditioning pulse and inversely related to the postconditioning interval. Yet, inhibition could be demonstrated long after (> 1 sec) the end of the conditioning pulse. Electrotonic inhibition was found at all diastolic intervals and did not depend on the presence of a previous action potential. In Purkinje fibers, conditioning action potentials led to active inhibition of subsequent responses. In contrast, in muscle cells, such action potentials had a facilitating effect (active facilitation). Electrotonic inhibition and active facilitation were observed in both sheep ventricular muscle and guinea pig ventricular myocytes. Accordingly, during repetitive stimulation with pulses of barely threshold intensity, we observed: (1) bistability (i.e., with the same stimulating parameters, stimulus: response patterns were either 1:1 or 1:0, depending on previous history), and (2) abrupt transitions between 1:1 and 1:0 (absence of intermediate wenckebach-like patterns). Simulations utilizing an ionic model of cardiac myocytes support the hypothesis that electrotonic inhibition in well-polarized ventricular muscle is the result of partial activation of Ik following subthreshold pulses. On the other hand, active facilitation may be the result of an activity-induced decrease in the conductance of IK1. Conclusion: Diastolic excitability of well-polarized ventricular myocardium may be transiently depressed following local responses and transiently enhanced following action potentials. On the other hand, diastolic excitability decreases during quiescence. Active facilitation and electrotonic inhibition may have an important role in determining the dynamics of excitation of the myocardium in the presence of propagation abnormalities. 相似文献
95.
成人先天性胆管扩张症手术治疗 总被引:20,自引:0,他引:20
目的 探讨成人先天性胆管扩张症手术治疗的经验体会。方法 回顾分析1985年1月至2004年12月中国医科大学附属第一医院普外科收治的成人先天胆管扩张症68例手术治疗资料。依Flanigan分型:Ⅰ型59例,Ⅱ型3例,Ⅳ型6例。所有病例均行囊肿切除,结果 术后发生胆汁漏6例。胰漏3例,急性胰腺炎2例。死亡2例,56例经1-20年随访,随访率为82.3%。5例表现轻度胆管炎,2例吻合口狭窄。余下49例均痊愈,无胆管炎及胆管狭窄表现。结论 囊肿切除、胆管空肠Roux-en-Y吻合是成人先天性胆管扩张症的首选治疗。切除囊肿时,囊肿近端在尽量切净囊肿基础上行大口吻合,防止术后吻合口狭窄;囊肿远端在保证睫液引流通畅、不损伤胰管开口的基础上,尽量切净囊肿内膜。 相似文献
96.
97.
D. Nowakowska B. Stray-Pedersen E. piewak W. Sobala E. Maafiej J. Wilczyski 《Clinical microbiology and infection》2006,12(9):913-917
This study investigated the prevalence of specific Toxoplasma gondii IgG in pregnancy, the incidence of congenital toxoplasmosis and the prevalence trend of T. gondii infection among pregnant Polish women between 1998 and 2003. The study population comprised 4916 women who were admitted to the Polish Mother's Memorial Hospital Research Institute in Łódź. Their sera were tested for specific IgG and IgM antibodies to T. gondii, and the incidence of T. gondii infection was calculated from the increase in prevalence rates of IgG antibodies in various age groups. Specific IgG antibody was found in 41.3% (95% CI 39.9–42.7) of pregnant women, and the prevalence of IgG increased with age. The linear trend was significant (p <0.001), with an annual seroconversion rate of 0.7% (95% CI 0.004–0.010). The risk of primary infection was estimated to be 0.5% for 9 months, i.e., an incidence of 5/1000 pregnancies. Assuming a 30% maternofetal transmission rate, 1.5/1000 neonates were infected in utero. Seroprevalence during the 6-year study period decreased from 45.4% in 1998 to 39.4% in 2003, with a yearly decline in prevalence of 1.0% (p 0.02). The most important contributory factor to this decline was the group of women aged 19–29 years, among whom seroprevalence decreased significantly (p 0.007). Specific IgM was found in 244 (4.9%) women. 相似文献
98.
99.
P A Zartner R P Handke A M Brecher M B E Schneider 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2007,9(3):192-193
A 4-year-old girl with post-surgical complete atrioventricular block received an epicardial dual chamber pacemaker system. During further growth intermittent exit block occurred, first misinterpreted as neurological seizures. The epicardial lead was replaced using a transvenous approach, and a pacemaker with an integrated home monitoring facility was implanted. After her discharge, a rise in the pacing threshold automatically initiated an event message. On the basis of this information, the patient was called in and imminent dislodgement of the ventricular lead was diagnosed by x-ray. The lead was repositioned and was found stable over 1-year follow-up. 相似文献
100.
Mark D. Rodefeld Mark Ruzmetov Marcus S. Schamberger Donald A. Girod Mark W. Turrentine John W. Brown 《European journal of cardio-thoracic surgery》2005,27(6):949-955
Objective: The infant with a functional single ventricle (SV) and unobstructed pulmonary blood flow (UPBF) requires early protection of the pulmonary vascular bed to ensure suitability for a subsequent Fontan procedure. Systemic obstruction by aortic arch obstruction, subaortic stenosis, or combination of both, has been widely recognized as an important risk factor for poor outcome in children with SV–UPBF who are palliated with pulmonary artery banding (PAB). We reviewed our experience with primary PAB in the subset of patients with SV–UPBF to identify risk factors for subsequent palliative procedures and Fontan completion. Methods: Between January 1990 and May 2004, 80 patients (median age, 14 days) with functional SV and UPBF underwent PAB as their primary palliative procedure. Thirty-five neonates had concomitant aortic coarctation or interrupted aortic arch repair (44%). A Damus–Kaye–Stansel procedure was subsequently performed in 19 patients, and subaortic resection or ventricular septal defect or bulboventricular foramen enlargement was performed in five. Results: There were 4 operative deaths, and 15 late deaths. The actuarial overall survival is 84% at 1 year, 76% at 5 and 15 years. Follow-up is complete in all but six children at a mean interval of 4.9±3.7 years (range, 2 months–15 years). Thirty-seven patients (49%; 37 of 76) have undergone the hemi-Fontan procedure (with three hospital deaths) and 40 patients (53%; 40 of 76; 12 children without previous hemi-Fontan) have undergone the completion Fontan procedure without mortality or Fontan takedown. Conclusion: In infants with single ventricle physiology with or without systemic outflow obstruction and unobstructed pulmonary blood flow, a strategy of pulmonary artery banding carries acceptable operative and mid-term mortality in a high-risk group of patients. Pulmonary artery banding does not compromise performance of subsequent Damus–Kaye–Stansel procedure or completion Fontan palliation. 相似文献